The present invention relates to the field of microelectromechanical devices, and more particularly, to microelectromechanical optical switches.
Microelectromechanical (MEM) technology has been used in a wide range of applications. For example, MEM devices can be used to switch optical energy from the switch inputs to selected switch outputs. MEM optical switches, sometimes referred to as Optical Cross-Connect (OXC) switches can include an Nxc3x97N array of reflectors to reflect optical energy from any switch input to any switch output. For example, in a 2xc3x972 OXC, a selected reflector of the 2xc3x972 array can be used to reflect the optical energy from any switch input to any switch output. The selected reflector can be located in the array where the column associated with input and the row associated with the output intersect. The selected reflector can be placed in a reflecting position to reflect the optical energy from the input to the selected output. The other reflectors can be placed in a non-reflecting position so as not to impede the propagation of the optical energy from the input to the selected reflector and to the output.
Some conventional MEM OXC switches operate by orienting the reflectors of the array using magnetic fields. In particular, the reflectors therein may be oriented horizontally (in the plane of the substrate on which the reflector is located) in a non-reflecting position and vertically (orthogonal to the substrate) in a reflecting position. Therefore, to switch optical energy from an input of the OXC switch to an output thereof, the, selected reflector can be oriented vertically and the other reflectors are oriented horizontally. Magnetically actuated MEM OXC switches are described further, for example, in U.S. patent application Ser. No. 09/489,264 filed Jan. 21, 2000, entitled xe2x80x9cMEMs Optical Cross-Connect Switchxe2x80x9d, the disclosure of which is hereby incorporated herein by reference in its entirety.
Unfortunately, reflectors in some magnetically actuated MEM OXC switches may occupy a relative large portion of the substrate, thereby reducing the number of reflectors that may be included in the MEM OXC switch. For example, some magnetically actuated MEM OXC switches orient the reflectors in a horizontal position when the reflectors are in a non-reflective position as described above. Accordingly, the substrate may be over-sized to provide adequate space for all of the reflectors to be oriented horizontally on the substrate. Furthermore, magnetically actuated MEM OXC switches may have localized magnetic actuators located under each reflector. The localized magnetic actuators may, therefore, further increase the area of the substrate which may need to be allocated to each reflector. In view of the above, a need continues to exist to further improve MEM optical switches.
The present invention can allow improved Microelectromechanical (MEM) Optical Cross-Connect (OXC) switches by providing a plurality of reflectors, wherein the each of the plurality of reflectors is movable to at least one of a respective first reflector position along an optical beam path from an input of the MEM OXC switch to an output thereof and a respective second reflector position outside the optical beam path. A mechanical actuator moves to at least one of a first mechanical actuator position and a second mechanical actuator position. A selector selectively couples at least one of the plurality of reflectors to the mechanical actuator, wherein the at least one of the plurality of reflectors moves from the first reflector position to the second reflector position when the mechanical actuator moves from the first mechanical actuator position to the second mechanical actuator position.
The mechanical actuator can allow a MEM OXC having simplified interconnect therein. In particular, the mechanical actuator may reduce the need to include individual actuation control lines in the MEM OXC. For example, in one embodiment, the mechanical actuator can move all reflectors coupled to the mechanical actuator. Accordingly, the need for controlling which reflectors are actuated may be reduced.
In one embodiment, the mechanical actuator moves in a direction that is substantially perpendicular to a substrate on which the reflectors are located. In another embodiment, the mechanical actuator moves in a direction that is substantially parallel to the substrate on which the reflectors are located.
In a further embodiment, the flexible elements each have a first portion attached to the substrate and a second portion, spaced-apart from the first portion, attached to a respective one of the plurality of reflectors. Each of the plurality of flexible elements allows the attached one of the plurality of reflectors to move between the first and second reflector positions. In another embodiment, the flexible elements can include a third portion spaced-apart from the first and second portions and attached to the substrate.